Clearly there are opportunities to make this project work easier.
I am interested to know what sensor is located 30 meters away.
Plain copper is generally OK, it just means you have to clean the oxide layer off before soldering if oxide has built-up. Once copper has an oxide film on the surface its stable for centuries if kept dry. Its not suitable for outside use as moisture will attack it and make verdigris (copper carbonate).
All mains wiring is buildings is plain copper for instance.
Or just ... work!
See #15.
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Hello John,
Thanks for that info...
How will I calculate the wire resistance for varies AWG gauge single strand wires..
Is there any article or link you can share so that I can further read about it to gain more knowledge?
I too am planning to use single strand wires for my electronics project to build a burglar alert system for 4 doors controlled a ESP8266 and 4 x MC-38 door sensor.
Any additional information would be great to calculate the voltage and current drop based on the AWG of the wire.
Thanks in advance
You can google wire resistance tables to find resistance of any size wire.
However I know:
- 1000ft or #10 AWG copper wire = 1 ohm
- Every 3 wire sizes the resistance doubles (or halves)
1 foot of #10 = 0.001 Ω
1 foot of #13 = 0.002 Ω
1 foot of #16 = 0.004 Ω
1 foot of #19 = 0.008 Ω
1 foot of #28 = 0.064 Ω
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If you use wire diameters (or areas) you only need to memorize the resistivity of copper which is about 17 nanoohm-metres. Resistance/length = resistivity/area.
So for 1mm diameter R/len = 1.7e-8/(pi * 0.0005^2) ~= 0.022 ohms/m
From the wire dimensions you can also calculate the weight of copper and thus the likely cost too - not so easy with wire gauges. And if you are winding coils the dimensions are useful for sizing coil fill areas/volumes too - again wire gauge isn't useful for this.
You are of course correct. However for me I like the 1000' #10, 1 ohm as I can do the calculations in my head.
I do wish there was a metric equivalent though.
Well you get g ~= 10 in SI to compensate, if gravity is your thing!
And 1 atm ~= 10^5 Pa.
I guess there's probably a phone app for this anyway.
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